I had the mac long tube headers installed with an off road shorty h-pipe, my question is, the car seems a little sluggish, would it be because it doesn't have enough back pressure without the cats? I also have 4:10's and I am thinking about going with 3:73's, would that be a mistake? I do have an intake too in case that would be a question...any help would be greatly appreciated guys!! I haven't posted in a while..been out of town.

When did it start feeling sluggish? Did you already have the exhaust in place? Or was it right when you changed it out?

How did you handle the O2 sensor relocation when you swapped to long tubes? The O2 sensors are sensitive to how far they are from the engine. They may not be getting hot enough, keeping you from entering closed loop mode, and probably causing it to run rich too. If that is the case, you can switch to O2's with internal heaters, rather than relying on the exhaust to heat them up. A tuner/programmer would be able to identify if this is the problem - any shop that can do a tune would be able to just look at it for you.

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